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                                                                    Exhibit 10.9

EXECUTION COPY

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                       FOURTH AMENDMENT TO LOAN AGREEMENT

                              AND OMNIBUS AMENDMENT

                          Dated as of February 9, 2004

                                  in respect of

                              GIANT YORKTOWN, INC.

================================================================================

<PAGE>

                                FOURTH AMENDMENT
                                TO LOAN AGREEMENT
                              AND OMNIBUS AMENDMENT

         This FOURTH AMENDMENT TO LOAN AGREEMENT AND OMNIBUS AMENDMENT (this
"Amendment") dated as of February 9, 2004 is among GIANT YORKTOWN, INC., a
Delaware corporation (the "Borrower"), GIANT INDUSTRIES, INC., a Delaware
corporation ("Giant Industries"), GIANT INDUSTRIES ARIZONA, INC., an Arizona
corporation ("Giant Arizona", and together with Giant Industries, the "Parent
Guarantors"), WELLS FARGO BANK NEVADA, NATIONAL ASSOCIATION, a national banking
association, not in its individual capacity (except as specifically set forth
herein), but solely in its capacity as collateral agent (the "Collateral
Agent"), and each of the Persons listed on the signature pages hereto as a
Lender (each, a "Lender").

                                    RECITALS:

         A. The Borrower, the Collateral Agent and the Lenders have heretofore
entered into that certain Loan Agreement dated as of May 14, 2002 (as amended by
that certain Amendment to Loan Agreement and Omnibus Amendment dated as of May
22, 2002 (the "First Amendment"), that certain Second Amendment to Loan
Agreement and Omnibus Amendment dated as of October 28, 2002 (the "Second
Amendment"), that certain Third Amendment to Loan Agreement and Omnibus
Amendment dated as of December 20, 2002 (the "Third Amendment"), and as further
amended, supplemented or otherwise modified from time to time, the "Loan
Agreement"). Giant Industries and Giant Arizona have heretofore entered into
that certain Parent Guaranty Agreement dated as of May 14, 2002 (as amended by
the First Amendment, the Second Amendment, the Third Amendment and the Second
Amendment to Parent Guaranty Agreement dated as of October 15, 2003, and as
further amended, supplemented or otherwise modified from time to time, the
"Parent Guaranty"). Capitalized terms used, but not otherwise defined in this
Amendment, shall have those meanings assigned to such terms in Section 1 to the
Loan Agreement, as amended hereby.

         B. The parties hereto desire to amend the Loan Agreement and certain of
the other Operative Documents.

         C. All requirements of law have been fully complied with and all other
acts and things necessary to make this Amendment a valid, legal and binding
instrument according to its terms for the purposes herein expressed have been
done or performed.

         NOW, THEREFORE, in consideration of good and valuable consideration the
receipt and sufficiency of which is hereby acknowledged, the parties hereto do
hereby agree as follows:

SECTION 1. AMENDMENTS TO LOAN AGREEMENT.

         Section 1.1. Section 1. (a) Section 1 of the Loan Agreement shall be
and is hereby amended by amending and restating in their entirety the following
definitions to read as follows:

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Giant Yorktown, Inc.                          Fourth Amendment to Loan Agreement

                  ""Consolidated Funded Indebtedness" means, for Giant
         Industries and its Consolidated Subsidiaries, at any time, without
         duplication, the sum of: (a) all Indebtedness (other than undrawn or
         unfunded amounts under outstanding Surety Instruments and Indebtedness
         of the type described in clause (h)(ii) of the definition of
         Indebtedness, and, provided that Giant Industries is in compliance with
         Section 6A(u) of the Parent Guaranty, other than Indebtedness owed to
         Statoil pursuant to the Statoil Purchase Agreement), (b) obligations to
         redeem or purchase any stock or other equity security of Giant
         Industries or a Subsidiary, and (c) any guaranty obligations in respect
         of any of the foregoing."

                  ""Subordinated Notes" shall mean (i) the BNY $150,000,000
         Subordinated Notes issued under the BNY $150,000,000 Indenture, (ii)
         the BNY $200,000,000 Subordinated Notes issued under the BNY
         $200,000,000 Indenture and (iii) notes issued in refinancing of the BNY
         $150,000,000 Subordinated Notes and/or the BNY $200,000,000
         Subordinated Notes, in whole or in part, whether with the same or
         different noteholders and the same or different indenture trustees,
         provided that such refinancing notes (or the indenture or note purchase
         agreement, as applicable) (x) contain subordination terms at least as
         favorable to the Lenders as the BNY $150,000,000 Subordinated Notes
         and/or the BNY $200,000,000 Subordinated Notes being refinanced, and
         (y) contain other terms no more restrictive on the Company and its
         Subsidiaries than the BNY $150,000,000 Subordinated Notes and/or the
         BNY $200,000,000 Subordinated Notes being refinanced, including
         refinancings thereof. Notes shall not be considered "Subordinated
         Notes" unless and until the Collateral Agent shall have received copies
         of the documentation evidencing or relating to such notes evidencing
         the terms and conditions of subordination required hereunder."

         (b) Section 1 of the Loan Agreement shall be and is hereby further
amended by inserting in alphabetical order the following new defined terms:

                  ""Statoil" means Statoil Marketing & Trading (US) Inc."

                  ""Statoil Intercreditor Agreement" means that certain
         Intercreditor Agreement dated as of February 9, 2004 between Statoil
         and the "Administrative Agent" under the Giant Industries Credit
         Agreement."

                  ""Statoil Purchase Agreement" means that certain Grane Crude
         Oil Purchase/Sale Agreement 2004/2008 between Statoil and the Borrower,
         as the same may be amended in compliance with the terms of Section
         6A(u) of the Parent Guaranty."

         (c) Section 8.1(e) of the Loan Agreement shall be and is hereby amended
by adding the following as a new clause (iv) thereof:

                  "(iv) A "Default" or an "Event of Default" shall occur under
         and as defined in the Statoil Purchase Agreement; or"

                                      -2-
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Giant Yorktown, Inc.                          Fourth Amendment to Loan Agreement

SECTION 2. AMENDMENTS TO PARENT GUARANTY.

         Section 2.1. Section 6. (a) Subparagraph (c) of Section 6 of the Parent
Guaranty shall be amended by adding a new clause (xii) thereto to read as
follows:

                  "(xii) of any amendment to the Statoil Purchase Agreement,
         such notice to be given not less than 10 days prior to effective date
         of such amendment, and to be accompanied by a copy of such amendment."

         (b) The first sentence of subparagraph (n) of Section 6 of the Parent
Guaranty shall be and is hereby amended and restated in its entirety to read as
follows:

                  "Giant Industries shall maintain not less than $350,000,000
         principal amount of Subordinated Notes outstanding at all times
         throughout the Loan Term; provided, however, that Giant Industries
         shall be permitted to have a lesser amount outstanding to the extent
         Giant Industries prepays or redeems Subordinated Notes after February
         9, 2004 with the proceeds of equity offerings."

         Section 2.2. Section 6A. (a) Subparagraph (a) of Section 6A of the
Parent Guaranty shall be and is hereby amended by renumbering clause (x) thereof
as clause (xi) and adding a new clause (x) to read as follows:

                  "(x) Liens on crude oil supplied by Statoil pursuant to the
         Statoil Purchase Agreement, securing Indebtedness incurred or assumed
         for the purpose of financing all or any part of the cost of acquiring
         such property after February 9, 2004; provided, that (A) any such Lien
         has attached prior to acquisition of such property or attaches to such
         property concurrently with or within 20 days after the acquisition
         thereof, (B) such Lien attaches solely to the property so acquired in
         such transaction, (C) the principal amount of the debt secured thereby
         does not exceed 100% of the cost of such property, and (D) the
         principal amount of the Indebtedness secured by any and all such
         purchase money security interests in favor of Statoil shall not be
         increased in excess of the amount contemplated by the Statoil Purchase
         Agreement as in effect on February 9, 2004; and"

         (b) Clause (ix) of Subparagraph (e) of Section 6A of the Parent
Guaranty shall be and is hereby amended and restated in its entirety to read as
follows:

                  "(ix) Indebtedness in respect of purchase money obligations
         within the limitations set forth SECTION 6A(a)(viii) and (x)."

         (c) Subparagraph (k) of Section 6A of the Parent Guaranty shall be and
hereby is amended and restated in its entirety to read as follows:

                  "(k) Subordinated Notes. Giant Industries shall not, and shall
         not permit any Subsidiary to: (i) amend, modify or change, or consent
         or agree to any amendment, modification or change to, any of the terms
         of the Indentures, the Subordinated Notes or the guarantees executed in
         connection therewith, other than (A) any such amendment or

                                      -3-
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Giant Yorktown, Inc.                          Fourth Amendment to Loan Agreement

         modification which would extend the maturity or reduce the amount of
         any payment of principal thereof or which would reduce the rate or
         extend the date of payment of interest thereon, (B) ministerial
         amendments that do not affect the Lenders, including amendments
         pursuant to Sections 9.01(1) through 9.01(5) of the BNY $150,000,000
         Indenture and the BNY $200,000,000 Indenture, (C) amendments of any
         representation or warranty, covenant, obligation or default of Giant
         Industries to any holder of Subordinated Notes or to any trustee acting
         under the Indentures (including, without limitation, financial ratios)
         in a manner which either eliminates such representations and
         warranties, covenants, obligations or defaults or renders them less
         restrictive or onerous than those contained in the Subordinate Notes
         and/or the Indentures as in effect on February 9, 2004, and (D) such
         other amendments and modifications acceptable to the Required Lenders;
         or (ii) make any payments to the holders of the Subordinated Notes or
         to any trustee acting under the Indentures which is prohibited by the
         Indentures or (iii) make any prepayment of or redeem in whole or in
         part the Subordinated Notes, except with (1) proceeds of refinancing
         Subordinated Notes described in clause (iii) of the definition of
         "Subordinated Notes" or (2) proceeds of equity offerings (or any
         combination of refinancing or equity offerings)."

         (d) The following shall be added as a new Subparagraph (u) of Section
6A of the Parent Guaranty:

                  "(u) Giant Industries agrees that it shall not amend, and
         shall not permit the Borrower to amend, the Statoil Purchase Agreement
         in any manner that could, in the reasonable opinion of the Majority
         Lenders, adversely affect the Lenders."

SECTION 3. REPRESENTATIONS AND WARRANTIES

         In order to induce the Collateral Agent and the Lenders to enter into
this Amendment, the Borrower and the Guarantors each represent and warrant to
the Collateral Agent and to each Lender that:

                  (a) This Amendment, the Loan Agreement and the Parent Guaranty
         (each as amended hereby) and each other Operative Document have been
         duly authorized, executed and delivered by the Borrower and the
         Guarantors and constitute their legal, valid and binding obligations
         enforceable in accordance with their respective terms (subject, as to
         the enforcement of remedies, to applicable bankruptcy, reorganization,
         insolvency, moratorium and similar laws affecting creditors' rights
         generally and to general principles of equity).

                  (b) The representations and warranties set forth in Section 2
         of the Loan Agreement and Section 5 of the Parent Guaranty are true and
         correct in all material respects on and as of the Amendment Effective
         Date, after giving effect to this Amendment, as if made on and as of
         the Amendment Effective Date.

                  (c) As of the date hereof, at the time of and after giving
         effect to this Amendment, no Default or Event of Default has occurred
         and is continuing.

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Giant Yorktown, Inc.                          Fourth Amendment to Loan Agreement

                  (d) No approval, consent, exemption, authorization or other
         action by, or notice to, or filing with, any Governmental Authority is
         necessary or required in connection with the execution and delivery of
         this Amendment or the performance by the Borrower or any Guarantor of
         its obligations hereunder and under the other Operative Documents. This
         Amendment and the other Operative Documents have been duly authorized
         by all necessary corporate action, and the execution, delivery and
         performance of this Amendment and the other Operative Documents and the
         documents and transactions contemplated hereby does not and will not
         (a) contravene the terms of the Borrower's or any Guarantor's
         Organization Documents; (b) conflict with or result in any breach or
         contravention of, or result in or require the imposition or creation of
         any Lien under, the Subordinated Notes, the Giant Industries Credit
         Agreement, as amended, or any document evidencing any other material
         Contractual Obligation to which the Borrower or any Guarantor is a
         party or any order, injunction, writ or decree of any Governmental
         Authority to which the Borrower or any Guarantor is subject; or (c)
         violate any Requirement of Law.

                  (e) The execution, delivery and performance by Giant
         Industries and the Borrower of the Statoil Purchase Agreement and the
         documents and transactions contemplated thereby (including the Statoil
         Intercreditor Agreement to the extent applicable to Giant Industries
         and the Borrower) does not and will not (a) contravene the terms of the
         Borrower's or any Guarantor's Organization Documents; (b) conflict with
         or result in any breach or contravention of, or result in or require
         the imposition or creation of any Lien under, the Subordinated Notes,
         the Giant Industries Credit Agreement, as amended, or any document
         evidencing any other material Contractual Obligation to which the
         Borrower or any Guarantor is a party or any order, injunction, writ or
         decree of any Governmental Authority to which the Borrower or any
         Guarantor is subject, other than Liens in favor of Statoil to the
         extent provided in the Statoil Purchase Agreement as in effect on
         February 9, 2004; or (c) violate any Requirement of Law.

SECTION 4. EFFECTIVENESS.

                  This Amendment shall become effective on February 9, 2004 (the
         "Amendment Effective Date") upon the satisfaction of the following
         conditions precedent:

                  (a) Amendment. The Collateral Agent and the Lenders shall have
         received counterparts of this Amendment duly executed by Giant
         Industries, Giant Arizona, the Borrower, the Constituent Company
         Guarantors, the Collateral Agent, and the Required Lenders.

                  (b) No Default under, and Amendment of, Giant Industries
         Credit Agreement. Giant Industries shall have provided evidence
         satisfactory to the Collateral Agent and the Lenders that (i) the Giant
         Industries Credit Agreement has been amended pursuant to a Third
         Amendment thereto in form and substance satisfactory to the Lenders and
         (ii) no default or event of default shall exist under the Giant
         Industries Credit Agreement.

                                      -5-
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Giant Yorktown, Inc.                          Fourth Amendment to Loan Agreement

                  (c) Statoil Purchase Agreement. The Collateral Agent and the
         Lenders shall have received an executed copy of the Statoil Purchase
         Agreement, executed by Statoil and the Borrower in the same form as
         previously provided to the Lenders.

                  (d) No Material Adverse Effect. Except as disclosed in writing
         to the Collateral Agent and the Lenders prior to the Amendment
         Effective Date, no event or circumstance has occurred that has resulted
         or would reasonably be expected to result in a Material Adverse Effect.

                  (e) No Default. As of the Amendment Effective Date, no Default
         or Event of Default shall have occurred or be continuing.

                  (f) Payment of Fees. Giant Industries shall have paid the
         Amendment Fee in accordance with Section 5 and all accrued, unpaid
         fees, costs and expenses owed pursuant to this Amendment, the Operative
         Documents or any other agreement between the Parent Guarantors and the
         Borrower and the Collateral Agent or any Lender, to the extent then due
         and payable, together with Attorney Costs of the Collateral Agent to
         the extent then invoiced prior to or on the closing date of this
         Amendment.

                  (g) Other. The Lenders shall have received such other
         approvals, opinions and documents as the Lenders deem appropriate.

Upon satisfaction of the foregoing conditions precedent set forth in this
Section 4, the Collateral Agent shall notify Giant Industries and the Lenders in
writing, and the date set forth in such notice shall be the effective date of
this Amendment.

SECTION 5. AMENDMENT FEE.

         Giant Industries agrees to pay to the Collateral Agent for the account
of each Lender which timely executes a counterpart of this Amendment, an
amendment fee equal to 0.05% of such Lender's Commitment. Such amendment fee
shall be due and payable in full on the date of execution of this Amendment by
Giant Industries and such Lender, shall be fully earned when due and payable,
and shall be in addition to any other fee, cost or expense payable pursuant to
the Operative Documents.

SECTION 6. COSTS AND EXPENSES.

         Giant Industries agrees to pay on demand reasonable Attorney Costs of
the Lenders and the Collateral Agent and all other costs and expenses of the
Lenders and the Collateral Agent in connection with the preparation, execution
and delivery of this Amendment and the other documents and instruments
contemplated hereby.

                                      -6-
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Giant Yorktown, Inc.                          Fourth Amendment to Loan Agreement

SECTION 6. MISCELLANEOUS.

         Section 6.1. Guarantor Obligations. Each Guarantor hereby ratifies and
affirms in all respects it obligations under its guaranty and acknowledges that
such guaranty shall remain in full force and effect.

         Section 6.2. Construction. This Amendment shall be construed in
connection with and as part of the Loan Agreement and the other Operative
Documents, and except as modified and expressly amended by this Amendment, all
terms, conditions and covenants contained in the Loan Agreement and the other
Operative Documents are hereby ratified and shall be and remain in full force
and effect.

         Section 6.3. Headings and Table of Contents. The headings of the
Sections of this Amendment are inserted for purposes of convenience only and
shall not be construed to affect the meaning or construction of any of the
provisions hereof and any reference to numbered Sections, unless otherwise
indicated, are to Sections of this Amendment.

         Section 6.4. References. Any and all notices, requests, certificates
and other instruments executed and delivered after the execution and delivery of
this Amendment may refer to the Loan Agreement and the other Operative Documents
without making specific reference to this Amendment but nevertheless all such
references shall be deemed to include this Amendment unless the context
otherwise requires.

         Section 6.5. Counterparts. This Amendment may be executed in any number
of counterparts, each executed counterpart constituting an original but all
together only one Amendment.

         Section 6.6. Governing Law. This Amendment shall be governed by and
construed in accordance under the laws of the State of New York without regard
to conflict of law principles (other than Title 14 of Article V of the New York
General Obligation Law).

                      [Signature Pages begin on Next Page]

                                      -7-
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Giant Yorktown, Inc.                          Fourth Amendment to Loan Agreement

                    Executed and delivered as of this 9th day of February, 2004.

                                   GIANT YORKTOWN, INC., as Borrower

                                   By:  /s/ ROGER D. SANDEEN
                                       -----------------------------------------
                                       Name: Roger D. Sandeen
                                       Its:  VP & CAO

                                   GIANT INDUSTRIES, INC., as a Guarantor

                                   By:  /s/ ROGER D. SANDEEN
                                       -----------------------------------------
                                       Name: Roger D. Sandeen
                                       Its:  VP & CAO

                                   GIANT INDUSTRIES ARIZONA, INC. , as a
                                       Guarantor

                                   By:  /s/ ROGER D. SANDEEN
                                       -----------------------------------------
                                       Name: Roger D. Sandeen
                                       Its:  VP & CAO

                                      -8-
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Giant Yorktown, Inc.                          Fourth Amendment to Loan Agreement

                                   BLACK DIAMOND INTERNATIONAL FUNDING, LTD.,
                                       as a Lender

                                   By:  /s/ ALAN CORKISH
                                       -----------------------------------------
                                       Name:  Alan Corkish
                                       Title: Director

                                      -9-
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Giant Yorktown, Inc.                          Fourth Amendment to Loan Agreement

                                   TRS1 LLC, as a Lender

                                   By:  /s/ DEBORAH O'KEEFFE
                                      ------------------------------------------
                                      Name:  Deborah O'Keeffe
                                      Title: Vice President

                                      -10-
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Giant Yorktown, Inc.                          Fourth Amendment to Loan Agreement

                                   GMAC COMMERCIAL FINANCE LLC
                                      (SUCCESSOR BY MERGER TO
                                      GMAC BUSINESS CREDIT, LLC), as a Lender

                                   By:   /s/ L. M. STEVENS
                                       -----------------------------------------
                                       Name:  L. M. Stevens
                                       Title: Division Chief Credit Officer

                                      -11-
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Giant Yorktown, Inc.                          Fourth Amendment to Loan Agreement

                                   ORIX FINANCIAL SERVICES, INC., as a Lender

                                   By:   /s/ F. R. RUCKER
                                       ----------------------------------------
                                       Name:  F. R. Rucker
                                       Title: VP

                                      -12-
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Giant Yorktown, Inc.                          Fourth Amendment to Loan Agreement

                                   TRANSAMERICA EQUIPMENT FINANCIAL SERVICES
                                      CORPORATION, as a Lender

                                   By:  /s/ JAMES R. BATES
                                      ------------------------------------------
                                      Name:  James R. Bates
                                      Title: VP

                                      -13-
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Giant Yorktown, Inc.                          Fourth Amendment to Loan Agreement

                                   WELLS FARGO BANK NEVADA, NATIONAL
                                       ASSOCIATION, as Collateral Agent

                                   By   /s/ ERIC MORGAN
                                      ------------------------------------------
                                       Name:  Eric Morgan
                                       Title: Trust Officer

                                      -14-
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Giant Yorktown, Inc.                          Fourth Amendment to Loan Agreement

         Each of the undersigned hereby acknowledges and agrees to the terms of
the foregoing Amendment and further confirms its continued guaranty of the
obligations of the Borrower under the Loan Agreement, as amended hereby,
pursuant to the terms of its guaranty on this ______ day of February, 2004.

                                   GIANT FOUR CORNERS, INC.

                                   By   /s/ MARK B. COX
                                      ------------------------------------------
                                      Name:  Mark B. Cox
                                      Title: CFO
                                      Address: c/o Giant Industries, Inc.
                                               23733 North Scottsdale Road
                                               Scottsdale, Arizona  85255-3465
                                               Attention:  President

                                   SAN JUAN REFINING COMPANY

                                   By   /s/ MARK B. COX
                                      ------------------------------------------
                                      Name:  Mark B. Cox
                                      Title: CFO
                                      Address: c/o Giant Industries, Inc.
                                               23733 North Scottsdale Road
                                               Scottsdale, Arizona  85255-3465
                                               Attention:  President

                                   PHOENIX FUEL CO., INC.

                                   By   /s/ MARK B. COX
                                     -------------------------------------------
                                      Name:  Mark B. Cox
                                      Title: CFO
                                      Address: c/o Giant Industries, Inc.
                                               23733 North Scottsdale Road
                                               Scottsdale, Arizona  85255-3465
                                               Attention:  President

                                      -15-
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Giant Yorktown, Inc.                          Fourth Amendment to Loan Agreement

                                   GIANT MID-CONTINENT, INC.

                                   By   /s/ MARK B. COX
                                      ------------------------------------------
                                      Name:  Mark B. Cox
                                      Title: CFO
                                      Address: c/o Giant Industries, Inc.
                                               23733 North Scottsdale Road
                                               Scottsdale, Arizona  85255-3465
                                               Attention:  President

                                   GIANT STOP-N-GO OF NEW MEXICO, INC.

                                   By   /s/ MARK B. COX
                                      ------------------------------------------
                                      Name:  Mark B. Cox
                                      Title: CFO
                                      Address: c/o Giant Industries, Inc.
                                               23733 North Scottsdale Road
                                               Scottsdale, Arizona  85255-3465
                                               Attention:  President

                                      -16-